When you have played the game for more than 48 hours or beat Survival mode at level 1,000 go to the 'Character Selection' screen and change the colour scheme to the one indicated to enable the corresponding effect. This also works for EX characters and ALL GG modes (GG GGX and AC).

Unlock Black Character:Change the colour scheme to 'Slash' colour and select your character by pressing 'Dust'.

Unlock Gold Character:Change the colour scheme to 'Reload' colour and select your character by pressing 'Dust'.

When you defeat a character's Black EX form in the indicated Survival level or play through at least one path of their Story mode that characters EX version will become unlocked. Justice and Kliff do not have a EX version.